Various devices for clamping or securing cords, i.e., cord fasteners, are well known, for example, U.S. Pat. No. 3,132,390 discloses a plastic slide clamp suitable for fastening a draw string in a bathing suit or the like. The patented device comprises a housing having a lock element slidably disposed in a tapering cavity in said housing. The interior surfaces of the cavity and the lock element define a passage through which cord is threaded and in which the cord is clamped or wedged by manual movement of the lock element. The lock element is provided with projections which engage slots in the housing and hold the lock element therein.
U.S. Pat. No. 3,564,670 discloses a cord fastener having a lock element that comprises a clamping roller which is slidably engaged with and manually moveable in a tapering cavity disposed in a housing. The roller is retained in the cavity with a movable pin and slot arrangement.
U.S. Pat. Nos. 3,845,575 and 3,965,544 disclose cord fasteners having a manually movable lock element slidably engaged with and disposed in a tapering cavity in a housing. The fastener disclosed in the latter patent is provided with resilient arms having a spring action that urges the lock element into the locked position.
U.S. Pat. Nos. 4,156,574 and 4,328,605 disclose cord fasteners provided with spring means for biasing a lock element into a locked position. The device disclosed in U.S. Pat. No. 4,156,574 employs arms which act as feelers and urge the lock element into the locked position at all times. Similarly, the device disclosed in U.S. Pat. No. 4,328,605 employs a helical spring which biases the lock element into the locked position.
The above-described devices especially those including means for urging the locking element into the locked position, are of rather complicated construction and do not provide a simple, reliable, device that automatically locks and that can be inexpensively constructed and easily assembled.
In view of the foregoing state of the art it would be desirable to provide a reliable automatically locking cord fastener of simple, inexpensive construction and that more fully realizes the objects and advantages sought to be provided by the prior art.
The fasteners of the present invention are useful in various applications where it is desired to releasably clamp a cord element in a selected position such as a drawstring closure and they are particularly useful in connection with sporting goods, such as, backpacks or sleeping bags, outerwear, such as, hooded parkas, rainwear and the like.